Arguably the most successful grass-roots activism campaign of modern times was the decades-long effort to free Soviet Jews from repression and get them to Israel. As chronicled in Laura Bialis' powerful documentary, the plight of the "refuseniks" -- Jews who were relentlessly persecuted once they dared apply for emigration -- was almost invisible to the West until the late 1950s and early '60s, when activists seasoned by the civil rights movement focused their attention on it.

Over the next decade the cause blossomed worldwide, with the most prominent refuseniks -- known from writings, photos and movies smuggled out by tourists -- seen as heroes by people from across the political spectrum. The activism persuaded the U.S. government to make human rights a central issue in its negotiations with the Soviets.

Though a bit exhausting at nearly two hours long, Bialis' film is well told and impressively detailed, making clear the refuseniks' heroism without resorting to hagiography. One can only hope that future films about today's most pressing humanitarian crises have such unambiguously happy endings.